Currently, if you have an "unlucky" font in your brand guide, it will come out extremely small on both courses and orderforms. As you can see on the attached images some of the fonts are way too small, and there's no way to change this other than to choose a different font that is inherently bigger.

To me it seems weird, that we have a style guide, where we can specify various font sizes, but then in places other sizes are just, like the course curriculum on the right hand side of the lesson, it uses the Subheadline font, but in a size XS that is not defined in the style guide. The text field uses a size small font that also doesn't adhere to any of the small font sizes defined in the style guide.

So my suggestion is, that ALL fonts, both System text and what we type in in various places ourselves will adhere to the style guide font sizes.